Refrigerating apparatus



March 22, 1932.

G. ANDRESEN REFRIGERAT ING APPARATUS Filed May 2, 1927 2 Sheets-Sheet 1 March' 22, 1932. G ANDRESEN REFRIGERATING APPARATUS Filed May 2, 92 2 Sheets-Sheet 2 Patented Mar. 22, 1932 *NITED. STATES.

' rss'onsz' PATENT OFF-ICE GEORGE annnnsnn, or CHICAGO, ILLINOIS, ASSIGNOR 'ro w. B. ranmfor CHICAGO, nnmors s j REFBIGEBATING APPARATUS My invention relates more particularly,

though not exclusively, to refrigerating apparatus of the-so-called flooded type in which the evaporator element is substantially filled at all times, duringrefrigeration, with the liquefied refrigerating agent supplied thereto under the contrbl of any suitable means.

tion whereby the formation of an oil blanket upon the body of liquefied refrigerant sup-.

' a refrigerating system comprising as an element thereof anevaporator embodying my invention. Figure 2 is a plan view of the evaporator. Figure 3 is a.view in side elevation thereof, with a portion of the upper man- 5 ifold of the evaporator broken away and shown in section, the view being taken at the line 3 on Fig. 1 and viewed in the direction of the arrow; and Figure 4, an enlarged view in vertical, longitudinal, section of valve mechanism ensuring the supplying to the pipe leading to the evaporator of refrigerant ,when in liquefied condition only. I

Referring to the arrangement of parts shown in Fig. 1, 5 represents a compressor which may be of any desirable construction and which is shownas driven by the armature shaft 6- of an electric motor7, the shaft 6 carrying a cooling fan 8. The compressor 5 is shown as provided with compressed-gas outlets at opposite ends thereof which communicate with a pipe 9 opening into one end of a condenser coil 10 the other end of which opens into the upper end of. a receptacle 11 s from the lower end of which leads a pipe '12 opening into valve mechanism represented at 13, the outlet of this valve mechanism communicating with a pipe I l-which rises therefrom and opens into the bottom of an evaporator represented generally at 15.; The outlet of the evaporator communicates with a My primary object is toprovide a construcpipe 16 which opens into a pipe 17 between the ends of the latter, one end of this pipeopening into the suction side of the com-' pressor 5 and the other end into an electriccircuit-controlling device 18, such as is com monly used in refri crating apparatus of the general character a ve referred to and -by which the supplying of current to the motor 7 through the wires 19 and 20 is controlled responsive to the pressure of the gas issuing w from the evaporator.

The device-13 is of a common and well known type for ensuring the supplying to the pipe 14 of refrigerant in liquefied condition only, the device to this endbeing provided 66 with a needlevalve 21 controlling a port 22 1n communication with the pipe 14 and the position of which is controlled by a pivoted float 23 engaging this valve, the pipe 12 opening into the float chamber 24 through a port- 25. the provision of the apparatus just described ensuring the opening of the valve 21 r only when there exists in the float chamber 24 a body of liquefied refrigerant extending above the outlet 22;

Referring now to the construction of the evaporator 15 it comprises, in accordance with the illustrated preferred embodiment of my invention, two series 26 and 27 of tubes 28 and 29. respectively, each of which is fully open at its upper and lower ends. Extending across the lower, open, ends of the'tubes 28 and extending the full length of the series 26 thereof is a manifold 30 which communicates with these tubes through the lower open ends thereofa'nd also communicates with the pipe 14 which latter opens into the manifold through a side thereof. The series 27 of tubes 29 similarly communicates with a manifold 31, like the manifold 30. these manifolds be- 99 ing in communication with each other at intervals therealong by cross-connecting pipes 32. Y

Extending across the open tops of the pipes 28 and 29 of the series26 and 27 thereof,-re-

7 spectively, are trap-forming housings 33 and 34. respectively, in the form of hoodemanifolds. these housings being preferablv spaced throughout their side walls and tops from the upper ends of the pipes. The housings 33 and 34 are in communication with each other at intervals preferably at points below the upper ends of the tubes, through the medium of cross-connecting pipes 35, the outlet pipe 16, and forming an outlet for the evaporator,

opening into the interior of the housing 34 preferably at a point slightly below the up per extremities of the pipes 29.

One pipe of each of the series 26 and 27 thereof contains an opening 36 whereby communication is afforded between the housings 33 and 34 and -.the interiors of these pipes.

In the operation of the apparatus the refrigerant, supplied to the pipe 14 in liquefied condition, discharges therefrom into the manifolds 30 and 31 and thence into the tubes 28 and 29, (the pipe 14 preferably rising to a point at least as high as the upper ends of these tubes). In performing the refrigerating function the refrigerant supplied to the tubes as stated boils therein due to the heat of the surrounding relatively warm space to be refrigerated, the refrigerant and the oil mixed therewith in the operation of the compressor 5, discharging upwardly through the upper open ends of the tubes 28 and 29. Such of the refrigerant as becomes gasified in the evaporator is drawn off by'the action of the compressor 5, through the pipe 16, and the oil and such of the' discharging refrigerant as remains in liquefied condition, becomes separated from the gaseous refrigerant and descends in the housings33 and 34 wherein it is trapped. r In the normal operation of the apparatus there will exist in the bottoms of the traphousings 33 and 34 liquefied refrigerant to levels above the outlets 36 which preferably are of such size that the liquid refrigerant will not drain off through these-openings and into the tubes containing them, sufficiently fast to cause the levels of the liquefied refrigerant to lower below these openings. The accumulated oil floats on the liquefied refrigerant in these housings, and upon rising to the level of the outlets of these housings is drawn off with the gas by the action of the compressor 5.

It will be understood from the foregoing that by providing an evaporator in accordance with my invention the formation of an oil blanket through which the refrigerant, gasified in the evaporator, is required to be drawn by the suction action of the compressor, is avoided with the manifest advantage.

In this connection it may be stated that', the' normal functioning of the apparatus to avoid the formation of objectionable oil blankets in the'tubes will not be materially affected even should the level of the liquefied refrigerant in the housings 33 and 34 extend below the openings 36 whereby oil collecting in the housings 33 and 34 flows into those of the tubes which contain the openings 36, due either to abnormal conditions existing in the operation of the apparatus when of the preferred construction above stated, or to an arrangement or proportioning of the parts resulting in the draining of the liquefied refrigerant from the housings at such a rate that the levels of the liquefied refrigerant in the housings neither normally-nor ever extend above the openings 36, as such oil is returned to one only of the tubes of each series, thereby positively precluding the possibility offorming oil-blankets on the liquefied refrigerant in the other tubes of the series.

While I, have illustrated and fldescribed a particular construction embodying my invention, I do not wish to be understood as intendlng to limit it thereto as the same may be variously modified and altered without departing from the spirit of my invention.

What I claim as new, and desire to secure by Letters Patent is:

1. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed therewith is supplied and having an opening adjacent its top,

and a trap-forming housing at the upper porv tion of said member and communicating with said opening, said housing being spaced lat erally from said,member and containing an upper gas and oil outlet below said opening in said element and a lower opening, the latter in communication with said member.

' 2. 'In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member open at its top and to which liquefied gas heavier than oil and mixed therewith is supplied, and a trapforming housing extending over the open top of said member and in'spaced relation thereto, said housing containing an upper gas and oil outlet located below the open, upper,-end of said member and a lower opening in communication with the interior of said member.

3. In a gas-liquefying apparatus, the combination of an evaporator to which liquefied gas heavier than oil and mixed therewith-is supplied and comprising a series of hollow members to which the mixture is supplied and each containing an outlet adjacent its top, and an oil-trap common to said members and in communication with said outlets, said trap containing an outlet through which the gas passes and an opening communicating with the interior of one of said members below said outlet in the latter.

4. In a gas-liquefying apparatus, the combination of an evaporator elementicomprising a hollow member to whichliquefied gas heavier than oil and mixed therewith is supplied and having an outlet adjacent its top, and a trap-forming housing into which said outletopens, said housing containing an out- I 5. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed therewith is supplied and having an, outletadjacent its top, and a housing into which said outlet opens and through which the gasified liquid passes, said housing containing an outlet for liquefied gas communicating with said member for conducting back to the latter liquefied gas {)lscharged into said housing from said memr'. W 6. In a gas-liquefying apparatus, theconr bination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed therewith is supplied and having an outlet adjacent its top,

and a housing into which said outlet opens and through which-the gasified liquid passes, -s'aid housing containing an oil outlet in verti-v cal spaced relation to the bottom of said housing, and also containing a liquefied gas outlet below said oil outlet and communicatingwith said member for conducting back to the latter liquefied gas discharged into said housing from said member.

7. In a gas-'liquefying apparatus, the combination of an evaporator element comprising a hollow member, means comprising a compressor for supplying to said element liquefied gas heavier than oil and mixed therewith, said element having an opening adjacent its top, and a hood over the upper portion of said member and spaced laterally therefrom and containing a discharge outlet located below said opening and in communication with said compressor.

8. In a gas-liquefying apparatus, the com bination of an evaporator element compris-' ing a hollow member, means comprising a compressor for supplying to said element liquefied gas heavier than oil and mixed therewith. said element having an opening adjacent its top, and a hood over the upper portion of said member and spaced laterally therefrom throughout the area of its side wall and containing a discharge outlet located below said opening and in communication with said compressor.

9; In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member open at its top, means comprising a compressor for supplying to said element liquefied gas heavier than oil and mixed therewith, and a hood extending over.

the top of said member and spaced laterally therefrom and containing a discharge outlet located below.the open, upper, end of said member and in communication with said compressor.

10. In gas-liquefyingapparatus, the combination of an evaporator element comprising a hollow member, means comprising a compressor for supplying to said element liquefied gas heavier than oil and mixed therewith, said element having an opening adjacent its top, and a trap-forming housing at the upper portion of said member and communicating with said opening, said housing being spaced laterally from said memher and containing a dischargeoutlet located below said opening in said member and in communication with said compressor.

11. In a gas-liquefying apparatus, the coinbination of an evaporator element comprising a hollow member open at its top, means comprising a compressor -for supplying to said element liquefied gasheavier than oil -and mixed therewith, and a trap-forming hood extending over the top of said member in spaced relation thereto and containing a discharge outlet located below said opening in said member and in communication with said compressor.-

12. In a gas-liquefying apparatus, the combination of an evaporator apparatus comprising a hollow member having an outlet adjacent its top, means comprising a compressor for supplying to said member liquefied gas cent to, and surrounding, the top of said mem-' her, said housing containing an oil discharge outlet in vertically spaced relation to the bot-' tom of said housing and communicating with said compressor. V

14. The method of preventing the formation of an oil blanket on liquefied gas heavier than oil in an evaporating element to which liquefied gas mixed with oil is supplied, which consists in ejecting from the element the oil and llquefied gas at the top thereof by the boiling action of the contents of the element, separating the oil and liquefied gas and con-' ducting the gas evaporated from the liquefied gas and the separated oil away from the element.

15. The method of preventing the formation of an oil blanket on liquefied gas heavier than oil in an evaporating element to which the liquefied gas mixed with oil is supplied, which consists in ejecting from the element the oil and liquefied gas at the top thereof by the boiling action of the contents-of the element, separating the oil and liquefied gas and conducting the gas evaporated from the liquefied gas and the separated oil away from the element and returning the liquefied gas to the element.

1.6. The method of preventing the formation of an oil blanket on liquefied gas heavier than oil in an evaporator element to which the I liquefied gas mixed with oil is supplied which consists in ejecting from the element the oil and liquefied gas at the top thereof by the boiling action of the contents of the element and conducting the gas evaporated from the liquefiedgas away from the element at a point below that at which the oil and liquefied gas is ejected.

17. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavierthan oil and mixed therewith is supplied and having an outlet adjacent its top, and a housing into which said outlet opens and through which the gasified liquid passes, said housing containing a gas and oil outlet below the outlet of said hollow member and spaced from the bottom of said housing to cause said housing to function as a separating chamber.

18. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed therewith is i supplied and having an outlet adjacent its top, and a housinginto'which said outlet opens and through which the gasified liquid passes, said housing containing a gas and oil outlet below the outlet of said hollow member and spaced from the bottom of said housing to cause said housing to function as a separating chamber, said housing also containing a liquefied gas outlet below said gas and oil outlet and communicating with said member for conducting back to the latter liquefied gas discharged into said housing from said member.

19. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed with oil is supplied and having anoutlet adjacent itstop, and a trap-forming housing into which said outlet opens, said housing containing an outlet in vertical spaced relation to the bottom of said housing and below said outlet in said member and through which the gasified re frigerant and oil, by gravity, flow.

20. Ina gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member to which liquefied gas heavier than oil and mixed with oil is supplied and having an outlet adjacent its top and a housing into which said outlet opens and through which the liquefied gas passes,

said housing containing an oil and gasified refrigerant outlet in vertical spaced relation to the bottom of said housing and below said outlet in said member and also containing a liquefied gas outlet below said oil and gasified refrigerant outlet and communicating with said member for conducting back to the latter liquefied gas discharged into said houslng from said member.

21. In a gas-liquefying apparatus, the combination of an evaporator element comprising a hollow member, means comprising a compressor for supplying to said element liquefied gas heavier than oil and mixed therewith, said element having an opening adjacent its top, and a hood over the upper portion of said member and spaced laterally therefrom throughout the area of its side wall and containing an oil and gasified refrigerant outlet located below said opening and in vertically spaced relation to the bottom of said hood and in communication with said com- 

